I recently gave up on using the Sonicare DiamondClean Smart 9700 series (likely HX9954/56 or HX9954/74) that I got sometime around 2021-2022. The handle itself died, seemingly for no reason, losing all power and refusing to charge. Changing the battery seemingly requires de-soldering the battery from the motor, which is suboptimal.
I switched to an Oral-B iO Series 9, but I have experience with the DiamondClean, and I wanted to give some notes on it.
Sonicare is inferior to Oral-B's solution in terms of cleaning. I've linked the studies on the Oral-B page, but in-short, the cleaning is inferior to Oral-B's design.
During my ownership of the Sonicare, the
A3 replacement brush heads became available. Prior to this, they had a variety of brush heads serving a variety of roles, and A3 is effectively “the best brush head”. The bristles are relatively hard. All of the brush heads Sonicare sells are rather confusing, and the A3 seems to combine all of the benefits of all of the brushes into one brush.
The DiamondClean has a perplexing design. It comes with a wireless charger that's integrated with a rinse cup. The idea is that you can rinse your mouth with water using the cup and also charge the toothbrush with the same cup. The problem with this approach is that the cup generally gets dirty with water from the toothbrush after use. You must be extremely diligent with cleaning this, or it will cause the cup to get effectively permanent calcium deposits, if you have hard water. I could not remove mine even with vinegar and descaler.
If you opt to not use this for rinsing, it still gets damaged over time by water.
If you opt to not use this entirely, it's a pretty silly product to buy because the glass cup is actually quite nice, but it is very much designed to sit on the charger. If it's just on your counter, it's a very heavy cup.
Toothpaste easily accumulates underneath the attachment point where the handle connects with the head. Under this area is a plastic gasket that is vulnerable to some sort of either black fungus (mold?) or mineral deposit that chemically interacts with water and toothpaste. Left unremoved over time, this will accumulate disgusting black deposits that are effectively impossible to clean.
There is an app, and as of May 2025, you can sync with Apple Health using it.
In contrast to Oral-B, though, the travel case does have USB-A, which is kind of nice. The actual toothbrush is quite aesthetically pleasing. However, the general Sonicare line seems to have stagnated while Oral-B is at least moving forward with the new iO line.
Similar to Oral-B, there are a lot of brush modes that you probably won't use. They have a tongue cleaning brush, but it was honestly too much for me to handle.
I was pretty impressed with the battery life when I used it, but the cleanliness issues seem really offputting. Oral-B's design is fundamentally different, so I'm already happier with the Series 9 over the DiamondClean Smart 97xx series.